Figure 19.

Chemical structures of C(sp)-bonded XB donors (IEIB and BEIB), activated C(sp²)-bonded donors (1,4-DITFB and DBTFB), and nonactivated C(sp²)-bonded donors (DIB and DBB) cocrystallized using a solvent-drop grinding methodology. The six XB donor molecules are reported in order of decreasing V_S,max values (from left to right) associated with the most positive σ-hole on their halogen atoms. V_S,max values are the numbers reported near the corresponding atom and are given in kilojoules per mole. Adapted with permission from ref (209). Copyright 2013 John Wiley and Sons.